Data communication networks and systems generally transmit data at high rates over a plurality of circuits that include multi-pair data communication cable, such as electrically distinct twisted wire pairs. At high transmission rates, each wiring circuit itself both transmits and receives electromagnetic radiation so that the signals flowing through one circuit or wire pair may couple with the signals flowing through another wire pair. The unintended electromagnetic coupling of signals between different pairs of conductors of different electrical circuits is referred to as cross-talk. The problem of cross-talk increases as the frequency of the transmitted signals increases.
In telecommunication systems, twisted wire pairs are often terminated in modular plugs. For example, modular plugs for telephone use are very commonplace and must meet the electrical performance requirements of industry standards, such as IEC 603-7. A problem with such modular plugs is that although cross-talk between twisted wire pairs in the cable leading to the plug is generally at negligible or at least tolerable levels, an intolerable amount of cross-talk between the wires can exist in the plug. One of the reasons for this is that insertion of the twisted wire pairs into the plug and electrical connection of the wires to electrical contacts in the plug generally requires that the wires be untwisted for a certain length, thereby leaving the wires prone to cross-talk.
Connectors are known which try to eliminate or reduce the problem of cross-talk between twisted wire pairs of modular plug assemblies. An example of such a plug assembly is described in U.S. Pat. No. 5,628,647 to Rohrbaugh et al. Another example is a plug assembly manufactured by Hubbell Incorporated, Stonington, Conn., USA, under the name PAIR LOCK stable-twist plug assembly, described in the January 1999 catalog of Hubbell Premise Wiring. This plug assembly is purported to maintain pair twist much farther into the plug, thereby reducing the level of cross-talk. However, this plug assembly is only applicable for flat cables.